[Kingdom] Animalia Linnaeus, 1758 - animals
   Grade Enterozoa
     Grade Cœlomata
       Phylum Platyelmia
         Branch Suctoria
           I Class Trematoidea
           II Class Cestoidea - cestodes, tapeworms
           III Class Hirudinea Lamarck, 1818 - leeches see Subclass Hirudinida